Warming it up wouldn't speed up decomp too much? Would I do it with more water?
Decomp. is going to happen regardless of what you do, except during freezing. If the feeder is in the temp range of 41F - 140F bacteria is growing. You have four hours with a pink at room temp, then it's debatable if it could really harm your snake after that. I have left feeders over night, caught the snake feeding hours later and not noticed a problem. I'm sure their stomach flora is designed to break down bacteria that would make you and I, inhabitants of the lavatory.
What I would do, is get back to the basics. Check what's going on. Then let this guy sit for a little while. Maybe about a week. No handling, no poking, etc. Just change his water and thats it.
Then after a week, start utilizing the things Nanci and Betsy are telling you. Warming up one small pink, leaving him in the dark to eat it and checking on him in an hour. If he eats, then leave him alone. Wait five to six days and do it again. If he doesn't eat, then leave him alone, wait five to six days and try again.
Don't ever ever ever force feed. That's a last resort and shouldn't be attempted on an animal that has only gone a couple of weeks without eating. They can last a long time without food. My Anery went 7 months last year until he snapped out of it.
When you feed, slit the pinks. The smell alone may entice him. Make sure he isn't blue (in shed) before you feed. He may not want to eat during that time.
I'm sure he will snap out of this. Just give him a little time and be patient. In the mean time, read this thread here regarding a practical feeding method. It's called the Munson Plan. It's not perfect, but will suit the majority of snakes just fine.
http://www.cornsnakes.com/forums/showthread.php?t=50106
Good luck and keep us posted!
Wayne